...SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE MID-MISSISSIPPI
AND OHIO VALLEYS INTO MICHIGAN TODAY THROUGH EARLY TONIGHT...
The NWS Storm Prediction Center in Norman, Oklahoma is forecasting
the development of a few strong, long-track tornadoes over parts of
the Mid-Mississippi and Ohio Valleys into Michigan today through
early tonight.
The areas most likely to experience this activity include:
Illinois
Indiana
Northern and Western Kentucky
Lower Michigan
Ohio
Southeast Wisconsin
Surrounding this greatest risk region, severe thunderstorms will
also be possible from parts of Wisconsin, Iowa, Missouri, Arkansas,
Mississippi, Alabama, and Tennessee northeastward across much of the
Appalachians to the lower Great Lakes.
A potent jet stream disturbance with wind speeds in excess of 120
knots will sweep east across the central Plains today and across the
Ohio Valley and northern half of the Appalachians tonight. As this
occurs, a surface low now over the mid-Mississippi Valley will
rapidly intensify and accelerate northeastward, reaching northern
Michigan early tonight and western Quebec Monday morning.
East of the low, increasingly warm and humid air at the surface will
spread north across the Tennessee and Ohio Valleys, contributing to
very unstable conditions over a large part of the east central
United States. Coupled with daytime heating and ascent provided the
jet stream impulse, the environment will become very favorable for
severe thunderstorms --- especially along and ahead of fast-moving
cold front trailing southward from the low into the mid-Mississippi
and Ohio Valleys.
Given the degree of thermodynamic instability, and the strength and
character of the winds through the depth of the atmosphere, many of
the storms will become supercells. Some of these will be capable of
producing strong tornadoes --- in addition to large hail and swaths
of damaging surface winds.
The storms are expected to consolidate into one or two extensive
lines later today into tonight --- extending the threat for damaging
winds and isolated tornadoes eastward into the Appalachians by early
Monday.
State and local emergency managers are monitoring this potentially
very dangerous situation. Those in the threatened area are urged to
review severe weather safety rules and to listen to radio,
television, and NOAA Weather Radio for possible watches, warnings,
and statements later today.
..Corfidi.. 11/17/2013
